Bicycle brake systems typically comprise an actuating or brake lever assembly operatively connected by a control cable within a housing to a responding or brake arm assembly. The brake arm assembly includes a pair of brake arms or operating members pivotally attached to a bicycle frame element at one end and to the control cable at another end, each brake arm including a brake pad positioned such that the two pads sandwich the rim of a bicycle wheel. Actuation of the brake lever by a rider draws the brake arms toward each other until they clamp down on the rim thereby slowing the bicycle. In order to achieve responsive braking, the brake pads are positioned close to the rim with the lever in an undeflected position to reduce the travel of the pads during lever actuation. Consequently, the brake arms must be drawn apart from their adjusted position close to the rim to allow removal of the wheel. To allow the brake arms to be readily drawn apart, a quick release feature is typically included to disengage at least one brake arm from the control cable. The present invention is an improvement to quick release devices for brake control cables and the like.
Numerous types of bicycle brake mechanisms are known in the art including drum brakes, cantilever brakes, disk brakes, caliper brakes and linear-pull brakes. FIG. 1 depicts a conventional linear-pull brake system including a brake lever assembly 10 operatively connected by a control cable 20 within a cable housing 22 to a brake arm assembly 30. FIG. 2 is a front view of the conventional linear-pull brake arm assembly of FIG. 1. FIG. 3 is an isometric view of the quick release device of the linear-pull brake arm assembly of FIG. 1.
Typically, the brake lever assembly 10 consists of a brake lever 40 pivotally mounted at one end to a lever housing 42 attached to a bicycle handlebar 44. One end of the control cable 20 is operatively attached to the brake lever 40 at a cable attachment point 46 such that as the brake lever 40 is deflected by a rider's hand toward the handlebar 44, the tension on the brake cable 20 is increased thereby actuating the brake arm assembly 30.
A second end of the control cable 20 is secured by a cable anchor bolt 50 to one end of a first brake arm 60 pivotally attached about a pivot 62 to a first bicycle frame member 180. A first end of a yoke 70 is hingedly connected to a second brake arm 80 at pivot 81, the brake arm 80 pivotally connected to a second bicycle frame member 190 at pivot 82. First and second brake pads 90, 92 connected to brake arms 60, 80, respectively, are positioned on either side of a bicycle rim 94.
Typically, a first end of cable housing 22 abuts a barrel adjuster 86 operatively connected to lever housing 42, with a second end of cable housing 22 abutting a ferrule 112 located at a first end of a noodle 110. A barrel 95 located at a second end of the noodle 110 includes an attachment plate 96 configured to be removably coupled to a second end 84 of yoke 70, and a conical surface 98 configured to be removably coupled to a first end 101 of an elastically compressible bellows 100. The control cable 20 slides reciprocally within cable housing 22, noodle 110, ferrule 112, barrel 95, and bellows 100. As installed, a second end 103 of the bellows 100 is located proximate the cable anchor bolt 50. During lever actuation the bellows member 100 is compressed as the brake arms 60, 80 are drawn together.
The barrel 95 is configured to be removably inserted through an aperture 115 located at a second end 84 of the yoke 70, with a slot 113 extending from the aperture 115 to an edge of the yoke 70. Attachment plate 96 of barrel 95 is configured to abut the second end 84 of the yoke 70 as the remaining portion of the barrel 95 is inserted through aperture 115.
Typically, the brake arms 60, 80 are spring biased to pivot in an outward direction away from the rim 94. As installed, the brake pads 90, 92 are positioned proximate the wheel rim 94 such that when the brake lever 40 is deflected by a rider's hand, the brake pads will contact the wheel rim 94 thereby slowing the bicycle. Because the brake pads 90, 92 are positioned relatively close to the rim 94, the bicycle wheel cannot be removed from the brake arm assembly without first detaching the barrel 95 from the yoke 70 thereby allowing the outwardly biased brakes arms 60, 80 to pivot apart. In conventional brake arm assemblies this operation is achieved as follows. Initially, the first end 101 of the bellows 100 is be pulled apart from surface 98 of the barrel 95 by displacing the bellows in a direction X thereby breaking the seal formed between the barrel 95 and the bellows 100 and exposing the bare control cable 20. The barrel 95 is then retracted from aperture 115 of the yoke 70 in a direction Y. Finally, the barrel 95 is lifted in a direction Z as control cable 20 passes through slot 113 of the yoke 70. In order to reattach the barrel 94 to the yoke, this procedure must be repeated in reverse order. This rather cumbersome procedure makes it difficult to engage and disengage the barrel 95 from the yoke 70. Additionally, removal of the bellows 100 from the barrel 95 breaks the seal between these members exposing the bare control cable to moisture and allowing dirt and debris to become trapped inside the bellows, barrel, and noodle leading to premature wear, corrosion and reduced braking performance. Furthermore, repeated attachment and detachment of the bellows 100 to the barrel 95 causes the bellows to stretch and fray over time, preventing the bellows from fitting tightly onto surface 98 of the barrel 95 and resulting in a permanent loss of sealing.